JPH06202479A - Magnetic roll - Google Patents

Abstract

PURPOSE:To prevent an adhesive used in the case of fixing a grooved sleeve to a flange from obstructing the function of a magnetic roll without lowering workability by making the outside diameter of the calyx part of the flange smaller than the outside diameter of the sleeve, and setting a level difference part formed between the calyx part and the end of the sleeve as the accumulation part of the adhesive. CONSTITUTION:The level difference part B is formed between the calyx part 31 and the end 51 of the sleeve 5. The part B is used as the accumulation part where the projected part 6 of the adhesive applied to fix the sleeve 5 to the flange 3 is accumulated. Namely, in the case of inserting the sleeve 5 in the flange 3 after injecting the adhesive in a circumferential groove 33 for accumulating the adhesive, which is provided on the flange 3, the adhesive 6 leaked and projected from the groove 33 is accumulated in the part B. The shape of the part B is decided so that the projected adhesive 6 may not be projected to the outside from the outer peripheral surface of the sleeve 5. If it is projected to the outside from the outer peripheral surface of the sleeve 5, developer is stuck to the adhesive, thereby deteriorating image quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnet roll used to convey a magnetic developer.

[0002]

2. Description of the Related Art In a conventional electrophotographic apparatus, electrostatic recording apparatus, etc., a permanent magnet having a plurality of magnetic poles inside a non-magnetic sleeve is used as a means for conveying a magnetic developer, such as a developing roll or a cleaning roll. A magnet roll is often used in which members are arranged and both members are rotated relative to each other. Most of the magnet rolls have a structure as shown in FIG. In FIG. 4, 10 is a magnet 1 having a plurality of magnetic poles extending in the axial direction on its surface.
Is a magnet member fixed around the shaft 2.
The magnet 1 is made by, for example, molding a sintered ferrite magnet or integrally molding a mixture of a ferromagnetic powder and a resin by a method such as injection molding or extrusion molding, and has a diameter of 15 to 60 mm and a length. Is 200-35
It is often set to 0 mm. A flange 42 is attached to both ends of the shaft 2 via bearings 45.
A cylindrical sleeve 41 is fixed to the unit 2. On the surface of the sleeve 41, a plurality of grooves are often formed in the axial direction in order to improve the transportability of the magnetic developer. The cylindrical sleeve 41 is fixed to the flange 42 by applying the adhesive to the flange 42 (injecting the adhesive into the adhesive accumulating circumferential groove 43 of the flange 42), and
1 was inserted into the flange 42, and then the adhesive was cured by heat treatment or the like. As a related conventional technique, for example, Japanese Patent Publication No. 61-3027.
1 and JP-A-2-50182.

[0003]

In the above-mentioned prior art, since the adhesive reservoir circumferential groove 43 provided in the flange 42 is small (for example, width 1 to 2 mm, depth 0.5 to 1 mm), coating is performed. The adhesive thus adhered to the surface of the sleeve 41 sticks to the surface of the sleeve. In this way, the adhesive 44 adhered to the surface of the sleeve 41 may cause the function of the magnet roll to be hindered (the developer adheres to the protruding adhesive and the image quality is deteriorated). . Therefore, the protruding adhesive 44 must be removed. Conventionally, the removal of the adhesive 44 is performed by a wiping operation using a solvent, and the removing operation is troublesome and the workability is poor. It was

Therefore, the present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to fix a grooved sleeve to a flange without lowering workability. It is to prevent the adhesive from interfering with the function of the magnet roll.

[0005]

In order to achieve the above object, according to the first aspect of the invention, a cylindrical sleeve having grooves formed in the surface thereof at predetermined intervals in the axial direction and a sleeve provided inside the sleeve are provided. A magnetic member having a plurality of magnetic poles on the surface thereof, and a flange having an outer peripheral surface of the end portion and a flange portion fixed to the sleeve with an adhesive in a state where the end portion of the sleeve is in contact with the flange portion. In the magnet roll in which the sleeve and the magnet member rotate relative to each other, the outer diameter of the flange portion of the flange is made smaller than the outer diameter of the sleeve, and the flange is formed between the flange portion and the end portion of the sleeve. The stepped portion is used as the adhesive reservoir. Further, in the second invention, a cylindrical sleeve having grooves formed in the surface in the axial direction at predetermined intervals, a magnet member provided inside the sleeve and having a plurality of magnetic poles on the surface, and an end A magnet having a flange on its outer peripheral surface and a flange fixed to the sleeve with an adhesive in a state where the end of the sleeve is in contact with the flange, and the sleeve and the magnet member rotate relative to each other. In the roll, the outer diameter of the flange portion of the flange is made smaller than the groove bottom diameter of the groove formed in the sleeve, and the step portion formed between this flange portion and the end portion of the sleeve forms a reservoir for the adhesive. Part and

[0006]

According to the present invention, a step portion is formed between the flange portion of the flange and the end portion of the sleeve, and this step portion can be used as a reservoir for the adhesive to stick out and accumulate. In this case, the adhesive does not extend outside the outer peripheral surface of the sleeve, and therefore the adhesive used for fixing does not hinder the function of the magnet roll.

[0007]

Embodiments of the present invention will be described with reference to the drawings. The structure of the magnet roll according to the present invention will be described with reference to FIG.
FIG. 1A is a vertical sectional view of the magnet roll.
1B is a sectional view taken along line AA of FIG. The magnet roll 100 is formed by arranging a magnet member 10 formed by fixing a magnet 1 having a plurality of magnetic poles on its surface around a shaft 2 inside a cylindrical sleeve 5. The sleeve 5 is made of a non-magnetic metal material such as an aluminum alloy or stainless steel.

At both ends of the sleeve 5, a sleeve driving flange 3a and a sleeve concentric holding flange 3b are mounted. The flanges 3a and 3b are made of, for example, a nonmagnetic metal material such as an aluminum alloy. Then, both ends of the sleeve 5 are respectively inserted into the flanges 3a and 3b and fixed by an adhesive. Here, the flange 3a has a shaft 35 for transmitting a driving force from an external driving source (not shown) to the sleeve 5.
Bearings 4 are respectively fitted inside the flanges 3 a and 3 b, and the shaft 2 is supported by these bearings 4. By having such a structure, the sleeve 5 and the magnet member 10 can rotate relatively.

A photosensitive drum (not shown) is provided in parallel with the cylindrical sleeve 5, and the toner held on the outer periphery of the sleeve 5 is conveyed onto the electrostatic latent image on the developing portion of the photosensitive drum. , Is attached to the electrostatic latent image.
As shown in FIG. 2A, a plurality of grooves 50 are formed on the surface of the sleeve 5 at predetermined intervals in the axial direction.
The groove 50 is provided in this way in order to improve the transportability of the magnetic developer. 2 (b) is shown in FIG.
It is a cross-sectional view of the CC portion of (a).

The groove 50 is particularly effective in improving the transportability of the two-component developer composed of the magnetic carrier and the toner. Here, the magnetic developer used to convey the toner onto the latent image includes a one-component magnetic toner or a two-component developer including a magnetic carrier and toner. At this time, a rough surface is formed on the surface of the sleeve in order to improve transportability. However, when a one-component magnetic toner is used as the developer, spherical particles or amorphous particles are used for the blast treatment. In many cases, surface roughening treatment is performed by doing so. However, in the case of a two-component developer, the size of the carrier is large (the average particle size of the carrier: about 50 to 100 μm, the average particle size of the toner:
Approximately 5 to 10 μm), the developer transportability is not so improved by the blast treatment. Therefore, in the case of a two-component developer, it is preferable to form the groove 50 on the surface of the sleeve 5 as described above. However, this means that the present invention
It does not mean that it is not applied to developers other than the component developers.

A step portion B is formed between the flange portion 31 and the end portion 51 of the sleeve 5. This step portion B is the flange 3
It is used as a reservoir for the protruding portion 6 of the adhesive applied to fix the sleeve 5 to the sleeve. That is,
The sleeve 5 is fixed to the flange 3 by inserting the sleeve 5 into the flange 3 after injecting the adhesive into the adhesive reservoir circumferential groove 33 provided in the flange 3.
At this time, the adhesive leaks from the adhesive-holding circumferential groove 33 and sticks out of the flange 3. The protruding adhesive 6 accumulates in the step portion B.

The shapes of the flange 3 and the sleeve 5 are determined so that the protruding portion 6 of the adhesive accumulated in the step portion B does not protrude to the outside of the outer peripheral surface of the sleeve 5.
This is because if the protruding portion 6 of the adhesive protrudes to the outside of the outer peripheral surface of the sleeve 5, the protruding adhesive impairs the function of the magnet roll (the protruding adhesive causes the developer to The image quality deteriorates because of adhesion).

Next, the relationship between the shapes of the flange 3 and the sleeve 5 will be described with reference to FIGS. 3 (a) and 3 (b). Flange 3
A flange portion 31 that supports the end portion 51 of the sleeve 5 is provided at b. The outer diameter (D1) of the collar portion 31 is smaller than the outer diameter (D2) of the sleeve 5. Furthermore, this collar part 3
It is preferable that the outer diameter (D1) of No. 1 is smaller than the groove bottom diameter (D3) of the groove 50 formed in the sleeve 5. In this way, a step portion B is formed between the flange portion 31 and the end portion 51 of the sleeve 5, and a protruding portion of the adhesive applied to fix the sleeve 5 to the flange 3 is formed on the step portion B. 6 is accumulated. In FIG. 1, the sleeve concentric holding flange 3b has been described as an example, but the same applies to the sleeve driving flange 3a.

[0014]

According to the present invention, since the adhesive does not stick out to the outside of the outer peripheral surface of the sleeve, it is possible to prevent the adhesive used for fixing from interfering with the function of the magnet roll. It is possible to improve the sex.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a magnet roll according to the present invention.

FIG. 2 is a diagram showing the shape of a grooved sleeve.

FIG. 3 is a diagram showing a relationship in shape between a flange and a sleeve.

FIG. 4 is a diagram showing a configuration of a conventional magnet roll.

[Explanation of symbols]

 1 Magnet 2 Shaft 3 Flange 4 Bearing 5 Sleeve 6 Overhanging part of adhesive B Stepped portion 10 Magnet member 50 Groove 100 Magnet roll

Claims (2)

[Claims] 1. A cylindrical sleeve having grooves formed in the axial direction at predetermined intervals on the surface, a magnet member provided inside the sleeve and having a plurality of magnetic poles on the surface, and an outer peripheral surface of an end portion. And a flange fixed to the sleeve with an adhesive in a state where the end of the sleeve is in contact with the flange, the magnet roll in which the sleeve and the magnet member rotate relative to each other. The outer diameter of the flange portion of the flange is made smaller than the outer diameter of the sleeve, and the stepped portion formed between the flange portion and the end portion of the sleeve is used as an adhesive reservoir. . 2. A cylindrical sleeve having grooves formed in the axial direction at predetermined intervals on the surface, a magnet member provided inside the sleeve and having a plurality of magnetic poles on the surface, and an outer peripheral surface of an end portion. A magnet roll having a flange portion fixed to the sleeve by an adhesive in a state where the sleeve end portion is in contact with the flange portion, and the sleeve and the magnet member rotate relative to each other, An outer diameter of the flange portion of the flange is made smaller than a groove bottom diameter of a groove formed in the sleeve, and a step portion formed between the flange portion and the end portion of the sleeve is used as an adhesive reservoir. A magnet roll characterized by that.